My mate finally decided to find out what had broken on his car, as you
can see from the picture the exhaust cam has snapped.




It turns out the outside stud on the cam cap no.4 has stripped the thread from
the head, result was the whole cap had lifted up unscrewing the other nut
too.

This must have been a problem before as someone has added extra washers to try and screw the nut down

But what can we do now, other than another head?
Can it be re-tapped?

Any ideas are most welcomed